﻿<blockquote class="extDef">NOTE&nbsp; Definition according to ISO/CD 10303-42:1992<br>
This function returns the scalar (or dot) product of two directions. The
input arguments can be directions in either two- or three-dimensional
space. The returned scalar is undefined if the input directions have
different dimensionality, or if either is undefined.</blockquote>

<blockquote class="note">NOTE&nbsp; Function adapted from <strong>dot_product</strong> defined in ISO 10303-42.</blockquote>

<blockquote class="history">HISTORY&nbsp; New function in IFC1.5</blockquote>
</blockquote>